Starter Relay Test Yamaha OX66 Saltwater Series II

[hotajax]

I have OX-66 Saltwater Series. I don't believe it has a solenoid, but does have a relay. Is there an easy way to test the relay? A shop repaired my starter, and he assures me that the Bendix drive jumps right out there. But he did caution me to check the relay. Any tips on on any fast ways to check the relay? I am not the expert on electricity, for sure. Any suggestions greatly appreciated. Hot Ajax

 

[SkunkBoat]

Relay/solenoid often interchangeable words. Even the "Bendix" is called a solenoid by some.

Basically, it is a remote electromagnetic switch. You apply power to the coil and it pulls(pushes) the switch closed (or open in some cases).

When you turn the key, a small current is applied to the relay to close the switch. When the switch is closed it connects the starter to the battery and a very large current thru heavy wires. The starter turns.
At the same time, the "Bendix" solenoid engages the flywheel. When you let go of the key, the spring in the Bendix retracts the gear from the flywheel (so the engine isn't always spinning the starter motor)

You can do the old trick with a battery jumper cable. Apply Positive 12v (using a heavy gauge jumper cable) to the positive terminal of the starter motor. (Bypass the relay)


It is possible that you have a poor connection to the battery. (this would explain why it work ok on the bench) This could be at the lugs at the battery or at the motor or it could be the wire itself. If the wire cannot carry enough current, the starter might try to turn but not have enough power to engage and turn the engine over. Inspect for GREEN spots along the entire length of your starting wires. Feel for spots that don't flex like the rest.

 

[hotajax]

Relay/solenoid often interchangeable words. Even the "Bendix" is called a solenoid by some.

Basically, it is a remote electromagnetic switch. You apply power to the coil and it pulls(pushes) the switch closed (or open in some cases).

When you turn the key, a small current is applied to the relay to close the switch. When the switch is closed it connects the starter to the battery and a very large current thru heavy wires. The starter turns.
At the same time, the "Bendix" solenoid engages the flywheel.

You can do the old trick with a battery jumper cable. Apply Positive 12v (using a heavy gauge jumper cable) to the positive terminal of the starter motor. (Bypass the relay)


It is possible that you have a poor connection to the battery. This could be at the lugs or it could be the wire itself. If the wire cannot carry enough current, the starter might try to turn but not have enough power to engage and turn the engine over.

SkunkBoat: So if I understand you, if I bypass the solenoid, and go right to the hot terminal on the starter, and the engine turns, then there is a problem with the relay? Thank you for answering. Hot Ajax

 

[SkunkBoat]

SkunkBoat: So if I understand you, if I bypass the solenoid, and go right to the hot terminal on the starter, and the engine turns, then there is a problem with the relay? Thank you for answering. Hot Ajax

or with your wire. ...re-read my post because I added some things

 

[Blaugrana]

Relay/solenoid often interchangeable words. Even the "Bendix" is called a solenoid by some.

Basically, it is a remote electromagnetic switch. You apply power to the coil and it pulls(pushes) the switch closed (or open in some cases).

When you turn the key, a small current is applied to the relay to close the switch. When the switch is closed it connects the starter to the battery and a very large current thru heavy wires. The starter turns.
At the same time, the "Bendix" solenoid engages the flywheel. When you let go of the key, the spring in the Bendix retracts the gear from the flywheel (so the engine isn't always spinning the starter motor)

You can do the old trick with a battery jumper cable. Apply Positive 12v (using a heavy gauge jumper cable) to the positive terminal of the starter motor. (Bypass the relay)


It is possible that you have a poor connection to the battery. (this would explain why it work ok on the bench) This could be at the lugs at the battery or at the motor or it could be the wire itself. If the wire cannot carry enough current, the starter might try to turn but not have enough power to engage and turn the engine over. Inspect for GREEN spots along the entire length of your starting wires. Feel for spots that don't flex like the rest.

@SkunkBoat - Going back to my voltage drop, if I used a jumper cable from my positive terminal on my cranking battery directly to the positive terminal on the starter motor, how can I test to see if I have a voltage drop still?

I know when measuring positive on battery to positive on starter relay, it measured 2v when cranking. When turning the key, I see the drop on the gauges. Cranking battery addresses the GPS turning off but voltage drop still exists.

 

[SkunkBoat]

@SkunkBoat - Going back to my voltage drop, if I used a jumper cable from my positive terminal on my cranking battery directly to the positive terminal on the starter motor, how can I test to see if I have a voltage drop still?

I know when measuring positive on battery to positive on starter relay, it measured 2v when cranking. When turning the key, I see the drop on the gauges. Cranking battery addresses the GPS turning off but voltage drop still exists.

What is the problem you are trying to resolve?

Does the motor start well on a single battery?


Did you resolve the gps turning off by isolating the House battery from the starter battery?
Is your concern with the House voltage or the starter voltage?
The Yamaha guage is displaying the starter battery voltage not the House voltage.
When you crank a motor, the battery voltage will drop somewhat. It will jump up when the motor starts because it is now being charged by the motor.

2v on the gauge sounds fishy if the motor starts. OH! You can't measure from "pos on battery to pos on starter relay". You have to measure from neg battery to the pos starter.

Honestly, I would not be concerned with the measurement but with the result.
If the motor is not cranking well, there could a bad connection or bad wire (these would result in a voltage drop).
The point of using jumper cables is to rule out bad wires (pos or neg) or connections...or in the OPs case the starter relay.

 

[seasick]

SkunkBoat: So if I understand you, if I bypass the solenoid, and go right to the hot terminal on the starter, and the engine turns, then there is a problem with the relay? Thank you for answering. Hot Ajax

Bendix is no relative of a solenoid. A starter solenoid is an electro-mechanical device that allows a small current to switch a large current It is part of the starter motor drive invented by Vincent Bendix and later licensed/rights purchased by General Motors.
From Wikipedia:
A Bendix drive is a type of engagement mechanism used in starter motors of internal combustion engines. The device allows the pinion gear of the starter motor to engage or disengage the ring gear (which is attached to the flywheel or flexplate of the engine) automatically when the starter is powered or when the engine fires, respectively.

The unique thing about the Bendix design is that in addition to in effect throwing the drive gear into the teeth of the flywheel, once the engine starts and the flywheel rotational speed exceeds the speed of the starter, the drive gear releases and retracts. If it didn't the starter would spin itself to death. It's simple and elegant.

 

[seasick]

Skunkboat said "What is the problem you are trying to resolve?

I too don't know what the problem is. Describe what the symptoms of your problem are

 

[SkunkBoat]

Bendix is no relative of a solenoid. A starter solenoid is an electro-mechanical device that allows a small current to switch a large current It is part of the starter motor drive invented by Vincent Bendix and later licensed/rights purchased by General Motors.
From Wikipedia:
A Bendix drive is a type of engagement mechanism used in starter motors of internal combustion engines. The device allows the pinion gear of the starter motor to engage or disengage the ring gear (which is attached to the flywheel or flexplate of the engine) automatically when the starter is powered or when the engine fires, respectively.

The unique thing about the Bendix design is that in addition to in effect throwing the drive gear into the teeth of the flywheel, once the engine starts and the flywheel rotational speed exceeds the speed of the starter, the drive gear releases and retracts. If it didn't the starter would spin itself to death. It's simple and elegant.

"Bendix" is a term often used to refer to the starter solenoid mechanism that engages the flywheel. it is an electro-mechanical device also. Instead of throwing a switch it engages the flywheel. it works the same way. Bendix was a brand name of a mechanical device that really ins't used anymore, but the name stuck...

 

[seasick]

We usually agree on most things but I have to disagree in this instance just to keep up my reputation as a pain in the neck The Bendix innovation is not electrical at all. It is a threaded gear on the motor shaft that has a small spring that keeps it retracted when the starter motor is not running.
When the starter motor is powered the shaft and the splined gear start to turn. The genius in the design is that due to the resting inertia of the drive gear, the gear doesn't want to rotate but the rotational energy has to go somewhere so it in effect 'unscrews' the gear on the shaft. That makes the gear extend outward and into the teeth of the ring gear on the flywheel. As Newton said, "An object at rest tends to stay at rest"

Once the gear engages the ring gear, it is held in place by the load of turning over the engine. Once the engine rotates faster than the starter rotates, that friction is reduced and the spring pushes the drive gear back on the shaft.
My Yami starter like a zillion others motors has a Bendix drive.

Just to cover all bases, there are some starter motor arrangements that don't rely on the Bendix design to engage and do have a mechanical activation arrangement that is powered by a solenoid.

 

[SkunkBoat]

We usually agree on most things but I have to disagree in this instance just to keep up my reputation as a pain in the neck The Bendix innovation is not electrical at all. It is a threaded gear on the motor shaft that has a small spring that keeps it retracted when the starter motor is not running.
When the starter motor is powered the shaft and the splined gear start to turn. The genius in the design is that due to the resting inertia of the drive gear, the gear doesn't want to rotate but the rotational energy has to go somewhere so it in effect 'unscrews' the gear on the shaft. That makes the gear extend outward and into the teeth of the ring gear on the flywheel. As Newton said, "An object at rest tends to stay at rest"

Once the gear engages the ring gear, it is held in place by the load of turning over the engine. Once the engine rotates faster than the starter rotates, that friction is reduced and the spring pushes the drive gear back on the shaft.
My Yami starter like a zillion others motors has a Bendix drive.

Just to cover all bases, there are some starter motor arrangements that don't rely on the Bendix design to engage and do have a mechanical activation arrangement that is powered by a solenoid.

Maybe you read it before I quickly edited it. I did say that an actual Bendix was mechanical.

The OP mentioned the "Bendix" was moving in and out
My point is that "Bendix" has been used as a substitute name for a starter solenoid that has an actuator that engages the flywheel.


number 6 is the solenoid and it engages the starter to the flywheel (in addition to energizing the starter)

I have smacked this with a bfw a dozen times on Dodge & Ford starters over 40 years

 

[seasick]

I feel much better. We still agree on most things.
I've hammered a few starters in my time.
These days on cars, I look under the hood and then close it! I barely recognize anything

 

[Blaugrana]

Thanks for the responses!

So, I am still researching whether the new starter motor that was installed is pulling too much voltage when it engages or it flagged another issue on my boat that I was not aware of prior to changing the starter.

Basically, I turn the key when the battery switch is to my cranking battery. Sometimes, it doesn’t drop more than to 11v, but other times I see it drop to 10v or below. For the first time since going with a cranking battery, my GPS turned off which is where this all began. It didn’t turn off yesterday when out but I made sure to run a bit on just the cranking battery.

The engine has no issue starting after 2 seconds or so but my fear is whether this issue will be more prominent when I update my electronics in the off season.

My plan is to switch to the add a battery with ACR as this switching is annoying. However, I am debating on just running new cables from the batteries to the switch and to the engine.

This thread was interesting as I kept Skunkboat’s feedback on the jumper cable in mind. When troubleshooting with old non cranking battery, I measured 2v between battery and starter whenever I cranked the engine.

Is there a way to flag the starter motor as bad even if brand new? Would measuring positive between the relay and starter motor vs red on battery to red on relay vs red on battery to red on starter motor help rule out a cable causing the issue vs the motor?

 

[SkunkBoat]

Is there a way to flag the starter motor as bad even if brand new? Would measuring positive between the relay and starter motor vs red on battery to red on relay vs red on battery to red on starter motor help rule out a cable causing the issue vs the motor?

I suppose if you have a 2v drop across a wire it may be a problem. If that is what you are measuring.

The point of the jumper cables is its a simple fast way to help rule out the wires....if you know what you are doing....

And don't forget, the negative wire could be the problem just as much as the pos.

 

[Blaugrana]

I suppose if you have a 2v drop across a wire it may be a problem. If that is what you are measuring.

The point of the jumper cables is its a simple fast way to help rule out the wires....if you know what you are doing....

And don't forget, the negative wire could be the problem just as much as the pos.

Understood - I need to measure again to see if the 2v drop stands still with new starter battery.

Is my thinking wrong that since I am seeing 2v between positive on battery to positive on starter that something between those two points could be my problem, such as a ground cable, positive cable or battery switch?

 

[seasick]

At this point, assuming you have checked the battery cables for bad or corroded connections, my suggestion would be to get your hands on a clamp on amp-meter and measure what the starting current is. Knowing that along with the total round trip length of the battery cable run and the gauge of the cables will allow you to calculate the expected voltage drop when cranking. It is possible that your battery cables are undersized.
You can do a similar test on the accessory feed to the helm to see if the excessive voltage drain is caused by the accessory feed or that feed is OK but the voltage it connects to at the battery switch is low.